{"affected":[{"defaultStatus":"unaffected","ecosystem":"cargo","packageName":"rustls","product":"rustls","source":"CNA: VulnCheck","vendor":"rustls","versions":[{"lessThan":"0.23.45","status":"affected","version":"0.23.13","versionType":"semver"},{"status":"unaffected","version":"0.23.45","versionType":"semver"}]}],"cveId":"CVE-2026-123613","cwes":["CWE-20"],"description":"Rustls from 0.23.13 before 0.23.45 accepts TLS 1.3 handshake messages at the wrong encryption level when they follow a key-changing message in the same record, because Deframer::aligned does not enforce RFC 8446 record-boundary alignment. A peer or on-path attacker can pack a plaintext EncryptedExtensions with the ServerHello, which rustls accepts unencrypted.","epss":null,"exploits":[],"kev":null,"metrics":[{"score":6.9,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":5.3,"severity":"medium","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}],"modifiedAt":1794101917574,"publishedAt":1794101917574,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc"},{"source":"CNA: VulnCheck","tags":["patch"],"url":"https://github.com/rustls/rustls/commit/5046bdf8a612b35a2c1a9e168054c1d5c65e7dd7"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/rustls-0.23.13-before-0.23.45-tls-1.3-handshake-encryption-level-bypass"}],"remediation":[{"kind":"fix","source":"CNA: VulnCheck","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/rustls/rustls/commit/5046bdf8a612b35a2c1a9e168054c1d5c65e7dd7"}],"revision":"f8af4f0c5d665fe128f5ed7c2b67557e7e55911c08638d981156bc7f7acde4e4","sources":[{"modifiedAt":1794101917574,"name":"CNA: VulnCheck","retrievedAt":1794103852341,"url":"https://www.cve.org/CVERecord?id=CVE-2026-123613"}],"ssvc":null,"status":"published","title":"Rustls 0.23.13 before 0.23.45 TLS 1.3 Handshake Encryption Level Bypass","updatedAt":1794103852341}